Paper Title
The Development of an Instrument Diagnostik Two Tier Multiple Choice to Identify Understanding Concept of Student's on Chemical Bonding Material

This study aims to to identify understanding the concept of students to the matter a chemical bond in class X PP MA As-Salman Allakuang. This research is divided into two stages namely the development stage of the diagnostic test instrument of two tier multiple choice and the use of a two tier multiple choice diagnostic test instrument for understanding of students' chemical concepts on chemical bonding materials. Development of diagnostic tests includes seven stages including: determination of test objectives, preparation of the test grille (kisi-kisi of test), writing item, reviewing and revising the test, trials test, analysis and interpretation, and assembling items into a set test. Identify understanding of chemical bond concept of students by using two tier multiple choice diagnostic test instrument then analyzed by Certanly Response Index (CRI) technique. Based on the use of two-tier multiple choice diagnostic test instrument, the result of identification of the concept of chemical bonding material of students are: not know concepts of 10,23%, misconception 38,24%, and know concepts 51,53%. Keywords - Diagnostic tests, two-tier multiple choice, CRI